Something completely unexpected happened when the Eagles played Sunday ﻿on an unseasonably chilly late-May night at Cricket Wireless Amphitheatre. The colder it got at the massive Chula Vista venue, where a steady wind made it feel even more biting, the hotter the 39-year-old band and its music became. As a result, what began as a frosty evening — temperatures were in the mid-50s when the show started at 7:45 p.m. and dipped to 49 degrees when it ended nearly three hours later — turned into a musical outing that exuded a welcome sense of warmth and celebration.

“(It’s) a hot and sultry night here in Southern California!” singer-guitarist Glenn Frey told the 15,000-plus audience, following the first two selections, the a cappella chestnut “Seven Bridges Road” and the twangy, country-rocking “How Long.”

Fifty-five minutes later, singer-drummer-guitarist Don Henley told the audience that the band would spend intermission “soaking our hands in hot water.” He didn’t seem to be joking.

In fact, yesterday’s daytime high temperature of 62 was as cold or colder than 25 of the 31 days San Diegans experienced here in January. That’s why there was added resonance when Henley sang Don’t your feet get cold in the winter time? during the Eagles’ third and final encore, “Desperado.” To their credit, the Eagles rose to the challenge.

Following a glossy, note-perfect opening segment that was delivered with characteristic precision but little vigor, the band kicked into high gear with Henley’s solo hit “Boys of Summer,” guitarist-singer Joe Walsh’s brassy “In the City” and Henley’s vintage soul homage “In the Long Run,” which concluded the first half of the show.

The second half began with the stirring a cappella lament, “No More Walks in the Woods.” It was followed by two other numbers from the Eagles’ 2007 album, “Long Road Out of Eden” — “Waiting in the Weeds” and “No More Cloudy Days.” Like the four other songs performed Sunday from “Eden,” the band’s first new studio album since 1979, each was delivered with a sense of commitment that seemed missing from the note-perfect but business as usual renditions of such fan favorites as “Peaceful Easy Feeling,” “Lyin’ Eyes’ and “Witchy Woman.”

Of course, spontaneity has never been a strong-suit of the Eagles, whose classic songs are marvels of craft and unerring attention to detail. But as the night air grew colder, the band’s playing became more loose and invigorating. It was almost as if the group’s efforts to stay warm — Frey zipped up his leather jacket and bassist-singer Timothy B. Schmit ﻿traded his suit jacket for a knee-length coat and a scarf — helped their music ignite.

Henley clearly had a ball playing drumrolls to punctuate Frey’s introduction of each band member. Walsh, always the Eagles’ live wire on stage, soared on “Walk Away,” “Funk 49” and “Rocky Mountain Way” (whose opening line he modified to Spent the last year / San Diego way). Henley’s “Dirty Laundry” and Frey’s “Heartache Tonight” were just as invigorating and had an atypical air of raw spontaneity.

Hmm. Does cold equal bold? If so, the suddenly soaring Eagles might do well to play more chilly outdoor shows more often.